Power control switch for pumping wells



1951 J. T. MONTGOMERY 2,573,372

POWER CONTROL SWITCH FOR PUMPING WELLS Filed Sept. 15, 1945 PatentedOct. 23, 1951 POWER CONTROL SWITCH FOR PUMPING WELLS v James T.Montgomery, Overton, Tex.

Application September 15, 1945, Serial No. 616,611

This invention relates to well pumping eq pment and more particularly toapparatus for controlling the power in emergencies when the latter issuddenly relieved of its load.

The principal object of the invention is to provide wholly automaticmeans of simple construction, associated with a pump jack of a well,which is maintained at all times in readiness for instantaneousoperation should for any reason the load on the jack be suddenlychanged, such for example as breakage or backing off of the rod line orsections thereof during pumping of a well.

After a well or a number of wells in a field have ceased flowing undernatural gas pressures, pro- 2 Claims. (Cl. 192-1165) 2 I for rockingmotion. The horsehead 12 on an end of the beam is conventionally curvedand has a cable l3 attached thereto to effect rectilinear duction ismaintained by installing pumping units of various types but which havein common the function of reciprocating a rod line in a well through themedium of a polished rod, to actutravel of the polished rod I4 whichreciprocates the rods in the well I5.

At the opposite end of the beam l l, a plurality of counter balances l6ar supported to partially offset the weight of the rods in the well IS.-A pitman I1 is eccentrically connected to the wheel I8, which latter isdriven by an engine l9.

' The foregoing describes a more or less seize-'- matic showing ofconventional well pumping equipment such as disclosed, for example, inFigure 3. of Patent No. 2,199,583, May '7, 1940 in order to properlydefine the relationship of the invention to such equipment.

The ignition circuit of engines of the type employed for well pumpingequipment being generally known to those versed in the art, suffice ittosay that to'close the circuit, the engine will cease to operate.

tion, increases in speed to a dangerous degree, I

often resulting in irreparable damage to the engine and equipment.

It is therefore the object of the invention to provide a normally openswitch connected in the ignition system of the pump operating enginenormally under tension, upon separation of the rod line in a well, tostop the engine.

With the foregoing objects as paramount, the invention has furtherreference to certain features of accomplishment which will becomeapparent as the description proceeds, taken in connection with theaccompanying drawingswherein:

Figure 1 is a side elevational view of a conventional well pumping rig,showing the invention thereon.

Figure 2 is a side elevational view of an open switch, illustrating themanner in which the same is closed by the invention upon breakage of arod line, and

Figure 3 is a detail view of the friction plate forming part of theinvention.

Continuing with a more detailed description a Jack frame on which issupported a beam ll i It being the purpose of the invention to stop theengine upon rod breakage, a switch circuit 20 is provided and extendedtothe jack frame l0 so that a knife switch 2| may be properly located toaccommodate the elements of the invention which latter, to be complete,includes the case 22 of the switch having an open front, on each side ofwhich is an inwardly directed flange a, these confronting flangesserving as stops for the door 23 which is hinged at 24 to the case 22,thereby prohibiting outward movement of the door 23 in relation to thecase and resisting the action of a spring 25, to which further referencewill be made later.

No claim is made herein to the switch 2i except that a switch ofsuitable design is required in the combination of elements serving tocarry out the purpose of the invention. However, to close the switch 2|to stop the motor IS, the cover 23 is required to strike or moveinwardly against the blade 2! of the switch and to accomplish this inthe emergencies described, the spring 25 is attached to the lower end ofthe cover 23 of the switch and to the end of this spring is attached aflexible line 26 preferably a link chain. Attached in turn to the end ofthe line or chain 26 is a flat metal plate 21, bifurcated at 28 so thatit may straddle the polished rod Id.

In practice, the rod clamp 29, which is aflixed to the polished rod l4and normally bears upon the collar 30 supported by the cables I3 israised so that the bifurcated plate 2'! may be thrust between theseelements whereupon the clamp is lowered so that the entire weight of thesucker 3 rod assembly is supported on the plate 21. There is littlelikelihood that the weight on the plate will be relieved unless breakageor separation of weight supported by the clamp 29, pressure will berelieved on the plate 21, and at once the spring 25 will act to withdrawthe plate from its position between the clamp 29 and collar 30 and in.so doing, will recoil and strike the cover 23 with considerable force,thrusting the same against and closing the knife switch 2 I-. Thisaction re.- sults in instantaneous stopping of the engine 19, preventingdamage thereto as described.

After reconnecting the rod sections in the well, pumping operationsmaybe resumed with the elements of the invention relocated in the mannerdescribed to protect the engine and equip ment against damage uponfurther breakage or separation of the rod assembly.

Manifestly, the construction as shown and described is capable of somemodification and such modification as: may be construedto fall withinthe scope and meaning of the appended claims is also considered to bewithin the spirit and intent of the invention;

.- What .is claimed is:

1. In emergency control equipment for well pumping apparatus, a stringof rods suspended me, well, a pivoted walking beam for reciprocatingsaid string of rods, a rod clamp connecting said string of rods to acollar on said rod string in juxtaposition to said rod clamp, abifurcated plate held frictionally between said rod clamp and saidcollar under the weight of said string of rods thereon, an engine foroperating said walking beam having anig'nition system, a battery and abattery circuit in said ignition system, a normally open switch in saidbattery circuit adapted, in closed position, to render said ignitioncircuit ineffective to operate said engine, a housing for said switchhaving a hinged cover, spring biasing means forming a connection betweensaid bifurcated plate and said switch housing cover tending to pull saidplate from its frictional engagement between said rod clamp and collarand adapted upon separation of said string of rods from said walkingbeam to recoil against said switch housing cover to thrust the latteragainst said switch to close the same.

'2. In emergency control equipment for well pumping apparatus, a stringof rods in a well, a walking beam for actuating said rods, 2. rod clampconnecting said rod string with said walking beam, acollar adjacent saidrod clamp on u said rod string, a plate retained frictionally betweensaid clamp and collar under the weight of rods imposed thereon, anengine for actuating said walking beam having an ignition circuitadapted, in closed position, to render said ignition circuiti-nefiective to operate, said engine, a normally open switch in saidcircuit, an operating blade for said switch, a housing for said switch,means hinged to said housing and engag eable with said operating bladefor actuating the same, spring biasing means connecting said hingedmeans and said plate and adapted .upon separation of said rod string torelease said plate and close said switch by recoil action against saidhinged means to actuate said switch operating blade JAMES T. MONTGOMERY.

REFERENCES orrnn The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

